Method of making planished sheets.



UNITED STATES PATENT OFFICE,

SAMUEL M. COOPER, OF MoKEESPORT, PENNSYLVANIA, ASSIGNOR T0 AMERICAN SHEET AND TIN PLATE COMPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPO- RATION OF NEW JERSEY.

METHOD OF MAKING ELANISI-IED SHEETS.

No Drawing.

To all whom it may concern Be it known that I, SA'MUEL M. Ooornn, of McKeesport, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Methods of Making Planished Sheets, of which the following is a specification.

My invention relates to the manufacture of what is known in the art as planished iron, and more particularly to the intermediate steps of making such materials.

One object of this invention is to provide an improved method having a novel series of steps whereby the manufacture of plani'shed sheets is simplified, the difficulties of making such materials are lessened and the cost of manufacture is reduced.

Another vide improved means for treating the sheets whereby the surfaces of the materials are provided with a coating of oxid of suflicient thickness to effectually prevent sticking of the sheets in later heating and hammering operations and a more uniform blue color is obtained.

Heretofore in the manufacture of planished sheets it has been the practice to clean and remove the scale from the surfaces of the rolled sheets by pickling and to then form a pile by stacking the pickled sheets one on top of another until a pile or pack of approximately seventy-five sheets is formed. The so formed pack is then enveloped with old or defective sheets to form a cover therefor, the so formed cover being bound in place by means of wire or similar material, and the covered pack is placed in a furnace, where it remains for from three and one-half to four hours or until it becomes heated to the desired temperature. The heated packs are withdrawn from the furnace, the envelop or cover is then removed therefrom and, .while still heated, the individual sheets are successively removed fro-m the pack, are swept with a broom to remove any foreign substance and at the same time are blued, the bluing operation being effected by the application of steam to the surfaces of the single separated sheets and by contact with the atmosphere.

Thebluing operation is for the purpose of obtaining sheets having a color as uniform as possible as well as to form a coating Specification of Letters Patent.

Application filed October 23, 1913. Serial No. 796,875.

"short time (usually object of my invention is to pro- Patented J an. 27, 1914s.

of oxid which acts to prevent sticking of the piled sheets in the later heating and hammering operations.

It is heated in a pack or pile and then removed singly from the heated pile, that the sheets first removed will be of a materially different temperature from the last of the sheets, and that owing to this fact the sheets will lack uniformity in color and thickness of the oxid coating.

After the bluing operation the sheets are again piled or formed into a pack, the envelop or cover being omitted in this case, and the entire pile is again placed for a about twenty minutes) in a furnace, to be again heated, the furnace being intentionally kept smoky to prevent undue oxidation. hen again heated the pile is removed and the entire pile or pack is taken to a hammer where the pack or pile is planished and finished under the hammer.

In making planished sheets in accordance with my improved method, the sheets are rolled and then pickled in the usual manner. The pickled sheets are then heated singly, (instead of in a covered pack) by passing them successively through one or more continuous heating furnaces, endless chains or equivalent mechanism being employed to carry the sheets through the furnaces which are about sixteen feet in length.

By slowly moving the sheets through a furnace in direct contact with the products of combustion the plates will be uniformly heated and by keeping the furnace smoky, oxidation of the sheets in passing through the so-formed non-oxidizing atmosphere of the furnace is avoided or is reduced to a great extent.

The heated sheets, as they emerge successively from the discharge end of the furnace, are brought into contact with a stream or series of jets of steam, and after passing therethrough are maintained in contact with the air of the atmosphere for a time interval of about fifteen seconds, these operations producing an oxid of a uniform blue color on the surfaces of the sheets and coolin them. The blued and cooled sheets, which continue their forward movement, successively pass into and through a second heating furnace of the continuous type in which apparent that when the sheets are I they are again heated in a smoky or nonoxidizing atmosphere and emerging there from are again subjected to the action of steam and then air, and therebyagain and further blued so as to provide a sheet having a uniform color, and successive sheets of the same uniform color, the color serving to determine the amount of oxid coating upon the sheets. The sheets Which again are cooled by the action of the steam and the air are then piled one on another to form a pack or pile, and the pile is placed Within a third furnace to be again heated, and after heating is removed therefrom to a hammer Where the pile of sheets is hammered to planish and finish the material in such pile, in the same manner as heretofore employed in finishing such materials.

The advantages of my invention Will be apparent to those skilled in the art.

7 By the use of my improved method seconds or sheets not uniform in color can be re-treated so that a large percentage of the product heretofore classed as second grade is re-finished and made into first grade materials.

By making the planished sheets by my novel series of steps a more uniform and tighter coating of oxid is formed upon the sheets which does not break or fracture in bending the sheets. It will also be readily seen that the amount of labor necessary is materially reduced, the cost of fuel is lessened and the process thereby cheapened.

Modifications in the steps of my improved method may be made Without departing from my invention.

The second heating and bluing operation in some cases, may be omitted and other changes may be made Within the scope of the appended claims.

I claim a 1. In the manufacture of planished sheets the steps consisting in passing the sheets singly and successively through the nonoxidizing atmosphere of a smoky continuous furnace, then passing the heated sheets singly and successively through an atmosphere of steam and then air, then reheating and again subjecting the sheets to the action of an atmosphere of steam and then of air, then forming a pile of the so-treated sheets, reheating the pile and planishing and finishing the reheated pile by hammering.

2. In the manufacture of planished sheets the steps consisting in passing the sheets 7 singly and successively through the nonoxidizing atmosphere of a smoky continuous furnace, then passing the heated sheets singly and successively through an atmosphere of steam and then air, then forming a pile of the so-treatedsheets, reheating the,

pile and planishing and finishing the reheated pile by hammering.

In testimony whereof, I have hereunto set my hand.

SAMUEL M. COOPER. lVit-nesses J. C. Bow,

GEO. \V. ROBINSON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. 0. 

